Flame-resistant clothing, or FR clothing as it is commonly referred to, is personal protective clothing designed for electricians and workers in the utility, oil, gas and petrochemical fields who are at risk of exposure to electric arc and flash fires. FR clothing provides thermal protection from electrical arcs or flash fires, reducing the degree of burn and body burn percentage in the event of such an exposure.

The National Fire Protection Agency's (NFPA) 70E is the Standard for electrical Safety Requirements for Employees Workplaces. It is the standard that requires employees to wear flame-resistant protective clothing wherever there is a possible exposure to electric arc flash. All Carhartt ® FR clothing is NFPA 70E compliant and each piece of clothing is designated with a HRC rating and an ATPV rating. The HRC is a rating range that is directly related to the ATPV. There are 5 HRC values ranging from 0 to 4, with 0 representing the least risk and a 4 representing the greatest risk. The ATPV value, measured in cal/cm2, is a rating that indicates the level of protection. The higher the rating the more protection the clothing provides.